When performing a total knee arthroplasty it is beneficial to intraoperatively decide on the viability of the posterior cruciate ligament. If the posterior cruciate ligament is functional then a knee joint prosthesis utilizing the ligament may be used. If, however, the ligament is non-functional and is removed, a posterior cruciate ligament substituting prosthetic knee joint may be desired to provide posterior tibial subluxation resistance.
Heretofore, to accommodate the intraoperative decision described above, two separate femoral components were required to be kept within the operating arena. One solution to this problem is addressed in U.S. Pat. No. 4,950,298. The '298 patent discloses a modular knee joint prosthesis wherein an augmentation plate may be connected during surgery to the femoral contact surface of a femoral component. The plate provides augmentation for the distal end of the femur and includes a triangle stop and transverse post which engages a ramp post on the tibial articulating surface to limit undesirable movement. A problem with the '298 patent is that the modular plate component combines the distal augmentation with the triangle stop and there may be instances where posterior subluxation resistance may be desirable without distal augmentation of the femur.